This invention relates to a floating caliper spot type disc brake, in particular for automotive vehicles, with a brake caliper axially slidably guided on a brake support member and arranged between arms of the brake support member, and a spring clamping the brake caliper relative to the brake support member radially.
In floating caliper spot type disc brakes, springs for clamping a brake caliper relative to a brake support member are necessary in order to maintain the guides of the brake caliper free from clearance and to thus prevent rattling of the brake caliper in its guides, for example, when the vehicle is subject to vibrations on an uneven road surface.
In a known floating caliper spot type disc brake of the type referred to, such as disclosed in French Pat. No. 1,348,468, the brake caliper rests on the backing plates of the brake shoes located on both sides of the brake disc, with the brake shoes being in turn guided on the arms of the brake support member fitting over the brake disc. The brake caliper is held in position by means of a leaf spring fitting over the radial outer edge of the brake caliper and having its ends detachably fastened to the arms of the brake support member. A disadvantage in this known floating caliper spot type disc brake is that the leaf spring is situated between the outer periphery of the brake disc and the inner edge of the vehicle wheel, that is at a location where the mounting space available for the brake caliper is, as a rule, very small. Another disadvantage in this known brake is that the brake caliper is displaced relative to the leaf spring as the brake shoes' wear increases progressively, so that the position of the center of gravity of the caliper relative to the plane of action of the leaf spring becomes progressively disadvantageous. Therefore, the leaf spring is required to have an increased initial preload to compensate for this disadvantage.